<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
      }
      .tab {
        position: relative;
        width: 150px;
        height: 40px;
        margin: 0 auto;
        background: #ed6a5e;
        border-radius: 10px 10px 0 0;
        /* 加上立体效果 */
        transform: perspective(40px) rotateX(30deg);
      }
      .tab::before,
      .tab::after {
        content: "";
        position: absolute;
        width: 10px;
        height: 10px;
        bottom: 0;
        /* background: #ed6a5e; */
      }
      .tab::before {
        left: -10px;
        background: radial-gradient(
          circle at 0 0,
          transparent 10px,
          #ed6a5e 10px
        );
      }
      .tab::after {
        right: -10px;
        background: radial-gradient(
          circle at 10px 0,
          transparent 10px,
          #ed6a5e 10px
        );
      }
      .box {
        position: relative;
      }
      .label {
        color: #fff;
        position: absolute;
        left: 50%;
        top: 60%;
        transform: translate(-50%, -50%);
      }
    </style>
  </head>
  <body>
    <div class="box">
      <div class="tab"></div>
      <p class="label">选项卡1</p>
    </div>
  </body>
</html>
